David K. Joyce

Downs Collection, Minerals of the Apatite Supergroup

I am pleased to offer the mineral collection of Dr. Robert T. Downs for sale, here on the website. Dr. Downs was born and raised in Canada and lived in many places across the country. Since a boy he was interested in minerals and mineralogy and has had several mineral collections over the years. Bob was a “late starter” and, after many years working on major construction projects as a supervisor and surveyor In British Columbia and the Yukon, he finally completed a degree in mathematics at the University of British Columbia, at the age of 30. Subsequently, he completed a masters degree and then a PhD in Mineralogy and Mathematics at Virginia Polytechnic. All through his life, he collected and studied minerals and was especially good at field collecting fine and interesting mineral crystal specimens. After post-doctoral studies at the Geophysical Lab in Washington, DC, he accepted a professorship at the University of Arizona, in Tucson. He has contributed much to the world of crystallography and mineralogy over the years, in the field of crystal structures, the RRUF project, supervision of dozens of masters and PhD students, as founding curator of the New Alfie Norville Gem and Mineral Museum in Tucson and in remote sensing and mineralogical analysis for extra terrestrial missions.
The Downs collection reflects his interests over the years, particularly with the Apatite Group of minerals, fluorapatite, vanadinite, mimetite, pyromorphite, etc. As well , other specimens are some very good personally collected specimens from Southern Arizona. There are a number of other pieces that just intrigued Bob for various reasons. Here are some of his mineral specimens.

This page will show excellent specimens of Fluorapatite, mimetite, vanadinite, pyromorphite, etc., that Dr. Downs found interesting.

All prices in Canadian dollars. For payment in US$, deduct 20% or multiply by 0.8.

Click on any of the following thumbnails to view a larger image of the specimen.

FluorapatiteDowns Collection, Minerals of the Apatite Supergroup
  • Item #29626
  • Fluorapatite
  • 7.3x4.3x4.0 cm
  • Largest Crystal Size: 57mm
  • $85.00
  • Sapo Mine
  • Goiabeira, Minas Gerais
    Brazil
  • RTD The Sapo Mine is famous for the peculiar, stepped and elongated crystals of fluorapatite such as these. A one-time find m10, or so, years ago, yielded a number of fine specimens such as this one. Oddly, some of the crystals are hollow and most are terminated by a pinacoid and one pyramidal form. Very light green. Sits JUST like this for display.
FluorapatiteDowns Collection, Minerals of the Apatite Supergroup
  • Item #20620
  • Fluorapatite
  • 3.9x2.6x2.4 cm
  • Largest Crystal Size: as above
  • $280.00
  • Shengus Mine
  • Gilgit-Baltistan
    Pakistan
  • RTD This amazing fluorapatite crystal is a single crystal with some stepped growth. It is a short hexagonal prism, terminated by first and second order pyramid forms. The crystal is largely gemmy, with some cloudiness near the middle portions. Near the bottom, there are small amounts of some very fine inclusions of what is probably fine, fibrous byssolite inclusions and some tiny, green, platy crystals of what is probably chlorite. Excellent example of this mineral with no colouring impurities!
FluorapatiteDowns Collection, Minerals of the Apatite Supergroup
  • Item #29620
  • Fluorapatite
  • 3.9x2.6x2.4 cm
  • Largest Crystal Size: as above
  • $280.00
  • Shengus Mine
  • Gilgit-Baltistan
    Pakistan
  • Here is a spectacular specimen representing fluorapatite! This is a single crystal with stepped growth, showing prominent pinacoidal termination on a hexagonal prism and modified by first and second order pyramids. The faces are lustrous with an crystal interior that is mostly gemmy with cloudiness near the center of the crystal. The are some inclusions of a needle-like mineral near the bottom, probably byssolite or some thing similar and a little chlorite attached to the base. Excellent! RTD
VanadiniteDowns Collection, Minerals of the Apatite Supergroup
  • Item #29609
  • Vanadinite
  • 4.4x3.8x2.7 cm
  • Largest Crystal Size: 20mm
  • $65.00
  • Touissit
  • Bou Beker
    Morocco
  • RTD A cluster of very large, beige, vanadinite crystals from this famous area of Morocco. The crystals show hexagonal outline with flat terminations. Dense!!